What are these “pimples” on the jet engine for?
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When looking into the General Electric CJ 805-23B jet engine, I have discovered that all forward section of the compressor is covered by a number of near identically looking "pimples". What are these tiny devices for, what are they doing? And why only front section of the compressor has them?
jet-engine feature-identification
asked Dec 10 '18 at 18:00
h22h22
5,39912867
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add a comment |
$begingroup$
When looking into the General Electric CJ 805-23B jet engine, I have discovered that all forward section of the compressor is covered by a number of near identically looking "pimples". What are these tiny devices for, what are they doing? And why only front section of the compressor has them?
jet-engine feature-identification
asked Dec 10 '18 at 18:00
h22h22
5,39912867
$endgroup$
add a comment |
$begingroup$
When looking into the General Electric CJ 805-23B jet engine, I have discovered that all forward section of the compressor is covered by a number of near identically looking "pimples". What are these tiny devices for, what are they doing? And why only front section of the compressor has them?
jet-engine feature-identification
asked Dec 10 '18 at 18:00
h22h22
5,39912867
$endgroup$
When looking into the General Electric CJ 805-23B jet engine, I have discovered that all forward section of the compressor is covered by a number of near identically looking "pimples". What are these tiny devices for, what are they doing? And why only front section of the compressor has them?
jet-engine feature-identification
jet-engine feature-identification
asked Dec 10 '18 at 18:00
h22h22
5,39912867
asked Dec 10 '18 at 18:00
h22h22
5,39912867
edited Dec 10 '18 at 21:21
h22
asked Dec 10 '18 at 18:00
h22h22
5,39912867
asked Dec 10 '18 at 18:00
h22h22
5,39912867
asked Dec 10 '18 at 18:00
h22h22
5,39912867
5,39912867
add a comment |
add a comment |
1 Answer
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They are the roots of the variable stator vanes that control the direction of the airstream as it enters each compressor stage to manage and optimize the angle of attack of the compressor blades in each stage. The vanes are connected to the ring shaped gang bar and somewhere around the circumference there is an hydraulic actuator, or a series of them, that drives the gang bar rings to move all the vanes connected to it at the same time. The hydraulic actuator is usually powered with pressurized fuel and is operated by the fuel control system to keep the vanes at the optimal rotational position.
This video (thanks, @Mackk) shows how the vanes operate:
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
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1 Answer
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1 Answer
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oldest
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$begingroup$
They are the roots of the variable stator vanes that control the direction of the airstream as it enters each compressor stage to manage and optimize the angle of attack of the compressor blades in each stage. The vanes are connected to the ring shaped gang bar and somewhere around the circumference there is an hydraulic actuator, or a series of them, that drives the gang bar rings to move all the vanes connected to it at the same time. The hydraulic actuator is usually powered with pressurized fuel and is operated by the fuel control system to keep the vanes at the optimal rotational position.
This video (thanks, @Mackk) shows how the vanes operate:
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
$endgroup$
add a comment |
$begingroup$
They are the roots of the variable stator vanes that control the direction of the airstream as it enters each compressor stage to manage and optimize the angle of attack of the compressor blades in each stage. The vanes are connected to the ring shaped gang bar and somewhere around the circumference there is an hydraulic actuator, or a series of them, that drives the gang bar rings to move all the vanes connected to it at the same time. The hydraulic actuator is usually powered with pressurized fuel and is operated by the fuel control system to keep the vanes at the optimal rotational position.
This video (thanks, @Mackk) shows how the vanes operate:
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
$endgroup$
add a comment |
$begingroup$
They are the roots of the variable stator vanes that control the direction of the airstream as it enters each compressor stage to manage and optimize the angle of attack of the compressor blades in each stage. The vanes are connected to the ring shaped gang bar and somewhere around the circumference there is an hydraulic actuator, or a series of them, that drives the gang bar rings to move all the vanes connected to it at the same time. The hydraulic actuator is usually powered with pressurized fuel and is operated by the fuel control system to keep the vanes at the optimal rotational position.
This video (thanks, @Mackk) shows how the vanes operate:
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
$endgroup$
They are the roots of the variable stator vanes that control the direction of the airstream as it enters each compressor stage to manage and optimize the angle of attack of the compressor blades in each stage. The vanes are connected to the ring shaped gang bar and somewhere around the circumference there is an hydraulic actuator, or a series of them, that drives the gang bar rings to move all the vanes connected to it at the same time. The hydraulic actuator is usually powered with pressurized fuel and is operated by the fuel control system to keep the vanes at the optimal rotational position.
This video (thanks, @Mackk) shows how the vanes operate:
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
edited Dec 12 '18 at 3:14
Wayne Conrad
1,19011011
1,19011011
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
answered Dec 10 '18 at 19:36
John KJohn K
17.7k12352
17.7k12352
add a comment |
add a comment |
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